This guide was originally shown to me by the lovely Nothing, and her version of it can be found here. This herb guide was copied from the books, so it definitely doesn't be long to me and I am not claiming it.The Herbal Tools of a Medicine CatBorage Leaves -
To be chewed and eaten. The plant can be distinguished by its small blue or pink star-shaped flowers and hairy leaves. Great for nursing queens as it helps increase their supply of milk. Also brings down fever.
Burdock Root -
A tall-stemmed, sharp-smelling thistle with dark leaves. A medicine cat must dig up the roots, wash off the dirt and chew them into a pulp, which can be applied to rat bites. Cures infection.
Catmint/nip -
A delicious-smelling, leafy plant that's hard to find in the wild; often found growing in Twoleg gardens. The best remedy for greencough.
Chervil -
A sweet-smelling plant with large, spreading, fernlike leaves and small white flowers. The juice of the leaves can be used for infected wounds and chewing the roots helps with bellyache.
Cobweb -
Spiderwebs can be found all over the forest; be careful not to bring along the spider when you take the web! Medicine cats wrap it around an injury to soak up the blood and keep the wound clean. Stops bleeding.
Coltsfoot -
A flowering plant, a bit like a dandelion, with yellow or white flowers. The leaves can be chewed into a pulp, which is eaten to help shortness of breath.
Comfrey -
Identifiable by its large leaves and small bell-shaped flowers, which can be pink, white or purple. The fat black roots of this plant can be chewed into a poultice to mend broken bones or soothe wounds.
Dock -
A plant similar to sorrel. The leaf can be chewed up and applied to soothe scratches.
Dried Oak Leaf -
Collected in the autumn and stored in a dry place. Stops infections.
Feverfew -
A small bush with flowers like daisies. The leaves can be eaten to cool down body temperature, particularly for cats with fever or chills.
Goldenrod -
A tall plant with bright yellow flowers. A poultice of this is terrific for healing wounds.
Honey -
A sweet, golden liquid created by bees. Difficult to collect without getting stung, but great for soothing infections or the throats of cats who have breathed smoke.
Horsetail -
A tall plant with bristly stems that grows in marshy areas. The leaves can be used to treat infected wounds. Usually chewed up and applied as a poultice.
Juniper Berries -
A bush with spiky dark green leaves and purple berries. The berries soothe bellyaches and help cats who are having trouble breathing.
Lavender -
A small purple flowering plant. Cures fever.
Marigold -
A bright orange or yellow flower that grows low to the ground. The petals or leaves can be chewed into a pulp and applied as a poultice to wounds. Stops infection.
Mouse Bile -
A bad-smelling liquid that is the only remedy for ticks. Dab a little moss soaked in bile on a tick and it'll fall right off. Was paws thoroughly in running water afterward.
Poppy Seeds -
Small black seeds shaken from a dried poppy flower, these are fed to cats to help them sleep. Soothes cats suffering from shock and distress. Not recommended for nursing queens.
Stinging Nettle -
The spiny green seeds can be administered to a cat who's swallowed poison, while the leaves can be applied to a wound to bring down swelling.
Tansy -
A strong-smelling plant with round yellow flowers. Good for curing coughs, but must be eaten in small doses.
Thyme -
This herb can be eaten to calm anxiety and frayed nerves.
Watermint -
A leafy green plant found in streams or damp earth. Usually chewed into a pulp and then fed to a cat suffering bellyache.
Wild Garlic -
Rolling in a patch of wild garlic can help prevent infection, especially for dangerous wounds like rat bites.
Yarrow -
A flowering plant whose leaves can be made into a poultice and applied to wounds or scratches to expel poison. You can also feed it to a cat to have it throw up deathberries if it has eaten any.
DO NOT ATTEMPT TO USE THESE HERBS TO TREAT YOUR CATS IRL. IT DOESN'T WORK. REALLY. 
